Radical Cascade Cyclization of Alkene‐Tethered Compounds: Versatile Approach towards Ring‐Fused Polycyclic Structures

Asian Journal of Organic Chemistry, Год журнала: 2023, Номер 12(5)

Опубликована: Апрель 8, 2023

Abstract Ring‐fused polycyclic structures widely exist in a myriad of natural products and pharmaceutical molecules. Consequently, the construction such from readily available substrates becomes an important researching topic organic synthesis. Triggered by addition radicals to (activated or unactivated) double bonds alkenes, subsequent intramolecular addition/cyclization leads compounds. Following this procedure, variety functionalized ring‐fused were formed. Great achievements have been witnessed recently. Those works provided efficient, atom economy, operational simple approaches toward versatile alkene‐based substrates. Here, we summarized recent on formation via radical‐triggered cascade reactions alkenes. Construction with no less than 3 fused rings developed during last decade included Review, corresponding mechanisms also discussed.

Язык: Английский

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Photocatalytic Cyclization Cascades by Radical Relay toward Pyrrolo[1,2-a]indoles: Synthesis, Mechanism, and Application

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(5), С. 3509 - 3524

Опубликована: Фев. 16, 2024

A photocatalytic annulation cascade of unactivated N-alkene-linked indoles with Langlois' reagent by a radical relay is developed at room temperature under blue LED irradiation. The reaction afforded series tri/difluoromethylated pyrrolo[1,2-a]indoles in moderate to good yields. DFT study suggests that the ascribed rhodamine 6G-induced cyclization involving vinyl addition-radical and hydrogen-atom-abstraction (HAA) processes, interestingly, are applied as fluorescent dyes into fluorescence spectrum live-cell imaging. This paper represents an initial example on cascades HAA process.

Язык: Английский

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Electrocatalytic Annulation–Iodosulfonylation of Indole‐Tethered 1,6‐Enynes to Access Pyrrolo[1,2‐a]indoles

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(10)

Опубликована: Янв. 9, 2024

Abstract We present the first example of electrocatalytic three‐component annulation–iodosulfonylation indole‐tethered 1,6‐enynes with arylsulfonyl hydrazides and KI for accessing various iodosulfonated pyrrolo[1,2‐ a ]indoles in moderate to excellent yields high stereospecificity. This electrosynthesis opens new avenues construction skeleton good functional group compatibility under environmentally benign condition. Based on control experiments cyclic voltammetry data, we suggested plausible reaction mechanism which included anodic oxidation, homolysis iodide, radical addition, 5 ‐ exo dig cyclization, coupling or nucleophilic attack iodide ions cascade.

Язык: Английский

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Trichloromethyl‐Radical‐Initiated Three‐Component Reaction of Alkenes with CHCl₃ and Quinoxalinones

Advanced Synthesis & Catalysis, Год журнала: 2023, Номер 365(5), С. 687 - 692

Опубликована: Фев. 8, 2023

Abstract An iron(II)‐catalyzed three‐component reaction was developed for the construction of trichloromethylated 3‐benzylquinoxalin‐2(1 H )‐ones. This conducted through trichloromethylation alkenes with quinoxalin‐2(1 )‐ones using commercially available chloroform as trichloromethyl radical source, which provided a convenient approach toward magnified image

Язык: Английский

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Synthesis of CF₃-Substituted N-Heterocyclic Compounds Based on C–H Activation-Initiated Formal [2 + 3] Annulation Featuring with a Latent Nucleophilic Site

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(11), С. 7828 - 7842

Опубликована: Май 22, 2024

Presented herein is a novel synthesis of CF

Язык: Английский

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Photocatalytic synthesis of azaheterocycle-fused piperidines and pyrrolidinesviatandem difunctionalization of unactivated alkenes

Organic & Biomolecular Chemistry, Год журнала: 2023, Номер 21(16), С. 3317 - 3322

Опубликована: Янв. 1, 2023

A variety of azaheterocycle-fused piperidines and pyrrolidines bearing CF3 CHF2 functionalities were obtained using CF3SO2Na CHF2SO2Na by visible light photocatalysis. This protocol involves a radical cascade cyclization via tandem tri- difluoromethylation-arylation pendent unactivated alkenes. Benzimidazole, imidazole, theophylline, purine, indole serve as applicable anchors, thereby enriching the structural diversity piperidine pyrrolidine derivatives. method features mild, additive-free transition metal-free conditions.

Язык: Английский

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Polychloromethylation‐Initiated Radical 1,2‐Aryl Migration of α,α‐Diarylallyl Alcohols via Visible‐Light Photoredox Catalysis

European Journal of Organic Chemistry, Год журнала: 2023, Номер 26(31)

Опубликована: Июнь 15, 2023

Abstract A visible‐light induced radical 1,2‐aryl migration of α,α‐diarylallyl alcohols was developed under mild and metal‐free conditions. Commercially available CHCl 3 CH 2 Cl were used as tri‐ dichloromethyl precursors. Structurally diverse β‐polochloromethylated ketones obtained in good to moderate yields via neophyl‐type rearrangement. Besides, the polychloromethyl group can be easily transformed into other useful functional groups.

Язык: Английский

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Radical Cascade Cyclization of Unactivated Alkene-Tethered Indoles with Aryldiazonium Salt and Sodium Metabisulfite to Access Azo- and Sulfonylated-2,3-Dihyro-1H-pyrrolo[1,2-a]indoles

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(13), С. 9123 - 9129

Опубликована: Июнь 28, 2023

A method for the construction of heterocyclic scaffold 2,3-dihyro-1H-pyrrolo[1,2-a]indoles via arylsulfonyl radical-triggered cascade cyclization unactivated alkene-tethered indoles in absence any external photocatalyst has been developed. This protocol features easily accessible starting materials such as sodium metabisulfite and aryldiazonium tetrafluoroborates at room temperature offers good functional group compatibility, enabling introduction various functionalized sulfonyl azo groups into pyrrolo[1,2-a]indoles.

Язык: Английский

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Metal-free polychloromethylation/cyclization of unactivated alkenes towards ring-fused tricyclic indolones and benzoimidazoles

Organic & Biomolecular Chemistry, Год журнала: 2023, Номер 21(35), С. 7079 - 7084

Опубликована: Янв. 1, 2023

Polychloromethylative cyclization of N-alkenyl indoles was developed under metal-free conditions to afford tricyclic pyridoindolones and pyrroloindolones in moderate good yields. In the reaction, commercially available CHCl3 CH2Cl2 were employed as tri- dichloromethyl radical sources. Moreover, dichloromethylated polycyclic benzoimidazoles can also be obtained standard conditions.

Язык: Английский

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Accessing pyrrolo[1,2-a]indole derivatives via visible-light-induced dearomatizative cyclization of indoles

Chemical Communications, Год журнала: 2024, Номер 60(37), С. 4902 - 4905

Опубликована: Янв. 1, 2024

Dearomatizative cyclization of indoles: a novel synthetic method for pyrrolo[1,2- ]indole derivatives through visible-light-induced cascade dearomatizative indoles with external nucleophiles has been developed.

Язык: Английский

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